During our Logic course in the Computer Science department at University of Verona, we used the textbook "Language, Proof and Logic" which comes with extra software to make it easier to grade assignments, understand the discipline and have a reliable practice platform you can use to make sure what you're doing is legal and correct. The book, for obvious reasons, lacks a collection of "solved" exercises to check against - all you can do is tell Fitch, Boole or Tarski's World to run a background check to make sure all your steps are logically valid. I have experienced first-hand, though, that during personal practice sessions, it would be immensely useful to have access to a set of solved exercises to check against if you're really stuck or if you want to see another person's interpretation of the problem at hand. I uploaded my logic exercises, from assignments and personal exercise, to make it easier for new students to approach the subject.
PLEASE NOTE: DO NOT UPLOAD THESE FILES TO THE GRADE GRINDER. The Grade Grinder, LPL's grading server, has an anti-cheat mechanism that checks whether the file you uploaded is indeed yours or if it is someone else's exercise. I have uploaded these files to the Grade Grinder for my own assignments so, if you upload them, the Grade Grinder will detect them as cheating and immediately notify your instructor. If you want to pass your Logic class, you really do not want this to happen. Please make sure to upload your own files started from scratch to the Grade Grinder platform exclusively.